South SFV Today

Stanford researchers have made a significant advancement in the field of nanoelectronics by developing an ultrathin conductor that could potentially enhance the performance and efficiency of future electronic devices. In a recent study published in Science, the team demonstrated that niobium phosphide can outperform copper as a conductor when reduced to films just a few atoms thick.

Asir Intisar Khan, who completed his doctorate at Stanford and is now a visiting postdoctoral scholar, stated, "We are breaking a fundamental bottleneck of traditional materials like copper." He explained that their niobium phosphide conductors could transmit faster and more efficient signals through ultrathin wires, potentially improving energy efficiency in data centers.

Niobium phosphide is classified as a topological semimetal. This means it conducts electricity throughout but has more conductive outer surfaces compared to its middle. As these films become thinner, they exhibit improved conductivity due to the greater contribution from their surfaces. Traditional metals like copper struggle with conductivity when thinned below 50 nanometers.

Eric Pop, Pease-Ye Professor in the School of Engineering and senior author on the paper, highlighted the importance of this development for high-density electronics: "Better materials could help us spend less energy in small wires and more energy actually doing computation."

The research indicates that niobium phosphide becomes superior to copper at thicknesses below 5 nanometers, even at room temperature. This discovery is particularly relevant as existing candidates for nanoscale conductors require precise crystalline structures formed at high temperatures. The non-crystalline nature of niobium phosphide allows it to be deposited at lower temperatures compatible with current chip fabrication processes.

Akash Ramdas, a doctoral student and co-author on the paper, remarked on this breakthrough: "Now we have another class of materials – these topological semimetals – that could potentially act as a way to reduce energy usage in electronics."

Despite its promise, niobium phosphide is not expected to replace copper entirely but may be used for very thin connections while paving the way for further research into other topological semimetals. Xiangjin Wu, another doctoral student involved in the study, emphasized ongoing efforts: "For this class of materials to be adopted in future electronics, we need them to be even better conductors."

Pop's team plans further testing by transforming their films into narrow wires to assess reliability and effectiveness for practical applications. He noted the potential impact: "This kind of breakthrough in non-crystalline materials could help address power and energy challenges in both current and future electronics."

The research was supported by various institutions including Stanford University and external organizations such as Ajou University and IBM T.J. Watson Research Center.

For further information or media inquiries, contact Taylor Kubota at Stanford University Communications via tkubota@stanford.edu.